Having vowed never to record again, one of pop's most lauded singer-songwriters, Joni Mitchell, is returning with a new album this year. A tribute album is also due for release and Radio 2 was recently granted a rare interview. Is this the resurfacing of just another rock relic or that rare event: a comeback worth waiting for?

Not one to shy away from controversy, our Joni. "To enjoy my music, you need depth and emotionality," she recently told one interviewer. "Those two traits are bred out of the white, straight males who control the press."

That's not to say she has much time for feminists either. In the same interview she called them "amazons", adding that the women's movement "created an aggressive-type female with a sense of entitlement that's a bit of a monster".

From her earliest incarnation as the sweet-voiced ingénue flower child - whose lithe frame seemed dwarfed by her acoustic guitar - to the politically-committed grandmother we see today, Joni Mitchell has always been big news.

She struggled with polio in childhood, started smoking at seven and gave up her baby daughter for adoption.

Her high-profile lovers have included Graham Nash, once of The Hollies, who wrote the song Our House while living with Mitchell on Lookout Mountain in LA, James Taylor and Jackson Browne.

She hung out with Bob Dylan on the legendary 1975 Rolling Thunder tour, developed a cocaine habit and fled, motoring across the United States without a driving licence in her urge to return to California.

Her songs have provided hits for a number of acts: Judy Collins took Both Sides Now to the top of the charts after Mitchell, at the behest of a mutual friend, sang it down the phone to her one night.

'Peerless'

Woodstock has been famously covered by Matthews Southern Comfort and Crosby, Stills, Nash and Young. Even Led Zeppelin were inspired, witness their Going to California. And Bill Clinton's daughter was named after the Joni Mitchell song, Chelsea Morning.

But just where in the musical pantheon does the 63 year-old singer sit? Well, journalist Mick Brown, whose Tearing Down The Wall of Sound: The Rise and Fall of Phil Spector, is about to hit the bookshelves, is clear.

"She's very high up there with Bob Dylan, Leonard Cohen and Tom Waits," he says. "Peerless, she was a trailblazer in terms of what the music industry allowed women artists to do. Of course, Joan Baez was already a renowned folk artist but Joni Mitchell went much further."

BBC 6 Music presenter and author Andrew Collins agrees: "It's not a bad place to be, especially for one whose rather shrill voice is certainly not everybody's cup of tea and the abstract jazz phase was seemingly designed to put us all off her in the 70s."

And what about that three-octave voice? In the morning of her career it was a thing of wonder, swooping and rising like an exotic bird riding the thermals.

Today, five or so years after nodes on Joni's larynx and other physical problems threatened to silence it forever, it has assumed the richness of patined wood: a jazzy, smoky sound at once world-weary and defiant.

'Audience's wrath'

Even so, not everyone was always impressed. Mitchell famously faced the audience's wrath at the 1970 Isle of Wight festival. Whether this was because of a lack of adequate sanitation, the £3 ticket price or just a case of rockers baiting a folkie, remains a moot point. Even so, it was an unedifying and unsettling spectacle.

But Mitchell belongs to that most select of all artistic groups, the happy few who have led their followers on a warts-and-all journey through life.

As Brown puts it: "By writing about the ageing process, she shows she's not a pawn of the music industry. Her work is full of confessional ardour and honesty." He says songs like Chinese Café, which opens with the great lines:

"Caught in the middle
Carol, we're middle class
We're middle aged
We were wild in the old days
Birth of rock 'n roll days
Now your kids are coming up straight
And my child's a stranger
I bore her
But, I could not raise her"

But that honesty has always been problematic, commercially at least. Refusing to compromise her artistic vision has lost Mitchell many fans over the years.

Those beguiled by "moons and Junes and Ferris wheels" in the late 1960s might have been wowed by albums like Ladies of the Canyon, Blue and the jazz-tinged Court and Spark, cited by Madonna as a major influence.

But they were reluctant to latch on to Mitchell's further groundbreaking forays into jazz and "world music" - Hejira and Don Juan's Reckless Daughter. When artists like Sting began to cover the same ground during the late-80s, Mitchell's irritation was obvious.

Speaking in 1988, she said: "When I began experimenting, people weren't ready for it. Once it's in its second and third generational stages, people can accept it... Sting is going over my territory."

Even a great fan like Brown admits: "She's an industrial strength moaner, complaining that she hasn't had recognition and has been passed over. I don't think that this is the case."

More recently, Mitchell has become increasingly political, berating the US Government over issues as diverse as the war in Iraq, genetically-modified food and the treatment of Native Americans.

And her influence has been incalculable. Besides Madonna, Prince and Annie Lennox, she continues to inspire a new generation of artists, among them KT Tunstall.

Mitchell's disenchantment with the music industry first surfaced in the late 1960s when she admitted "you never love music in the same way after you enter the business".

But even after stopping recording and performing in 2002 and concentrating on her other love, painting, it seems that the improbable is about to happen. A new album, Shine, will be released later this year. Expectation is already building.

"I can't wait to hear what she has to say," says Mick Brown. "She's a great artist, just like Picasso, and the arrival of a new album is an event."

And Collins sees Shine as a great opportunity to reach younger listeners. "If it really is a minimalist return to classic form, and if the rumoured political content - inspired by the Iraq war, so we hear - turns out to be substantial, she may even find a new audience."

In an era seemingly characterised by a more superficial pop style, Mitchell's return to song writing will be keenly awaited by her fans and, perhaps, win some newcomers. Just don't call the feisty and fabulous Canadian "the female Bob Dylan".